Fig. 8. Analysis of the S1 potential energy surface of 1. The term “dist” refers to the C1–C2 distance, and “dihed” refers to the dihedral angle between the C1–C2 bond and the aryl plane of pyrene. The different minima of the S1 potential energy surface are given by large blue circles (the S0 minimum is indicated by a black circle). Linear interpolations in internal coordinate (LIIC) pathways between the different critical points of the first excited-state potential energy surface of 1 are indicated by the blue line. The energies of the other electronic states along the LIIC pathways are given by black (S0), green (S2), and palatinate (S3) lines. Insets provide the molecular geometries of the three S1 minima, as well as the corresponding S0/S1 transition density. For all molecular structures, the C1–C2 bond of the carborane is shown in the plane of the paper.
